Railway-switch-point detector



April 29, 1924. 1,492,280

H. A. WALLACE RAILWAY SWITCH POINT DETECTOR Original Filed Dec. 4 1922 Y 1 INVENTOR 2 BY awn-M ,N-a. ATTORNEY Patented Apr. 29, isaa td If... 1 i

HERBERT A. WALLACE, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH. & SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

BAILVTAY-SWITCH-POINT DETECTOR.

Application filed December 4, 1922, Serial No. 604,661. Renewed August 22, 1923.

To all whom it may concern:

Be it known that I, HERBERT A. WALLACE, a citizen of the United States. residing at Pittsburgh. in the county of Allegheny and State of Pennsylvania, have invented oer tain new and useful Improvements in Railway-Switch-Point Detectors, of which the following is a specification.

My invention relates to apparatus for railway switch point detection, and particularly to apparatus for detecting that a train has trailed through a switch.

One object of my invention is to increase the safety of trains and vehicles moving over railway switches. It is customary in automatic block signal territory and at interlockings to provide a circuit controller operated by the switch, the intention of which is to so control signals that they will indicate stop unless the switch points are in safe relation to the stock rail. When, by error, a switch point is trailed through, the circuit controller is usually operated during the passage of the several wheels because the switch point is not so rigidly held against the stock rail but that the flange of said wheels may pass between the switch point and stock rail. The trailing of a switch in this manner frequently damages the switch point so as to render it unsafe for subsequent high speed train movements, but the switch circuit controller may, and sometimes does, return, after being trailed through, to such position that its contacts will cause a clear signal. I, therefore, provlde means for retaining the contacts in such posltions as to cause a restrictive slgnal indication after the switch has been trailed through, whether or not the switch springs back to a position which, in the present state of the art, would cause a clear or proceed signal.

I will describe three forms of point detecting apparatus embodying my invention, and will then point out the novel features thereof in claims.

In the accompanying drawings, Fig. 1 is a view, partly diagrammatic, showing one form of railway switch point detector embodying my invention. This View shows the switch in the reverse position. Fig. 2 is a view similar to Fig. 1 but with the switch in the normal position. Fig.3isaview similar to Fig. 2, but showing the effect of a train trailing through the switch when the switch is in the normal position. Fig. 4t is a view showing a modification of the device shown in Fig. 1 and also embodying my invention. In this view the switch is in the reverse position. Fig. l is a fragmental plan View showing .the operating bars of the switch circuit controller shown in Fig. l. Fig. 5 is a view simi'larto Fig. 4 but showingthe switclrin the normal position. Fig.- 6 is a View," similar to Fig. 5, but showing the effect of a train trailing through the switch. Fig-.7 is a view showing a modification of the device shown in Fig. 5 and also embodying my invention. 4

Similar reference characters refer to similar parts in each of the several views.

Referring first to Fig. 1', the reference character A designates a stock rail in the vicinity of a switch, which switch comprises amovableswitch rail or point shown at B. In this view the switch is in the reverse position. The motion of the switch rail B is controlled by means of a bridle rod C and a lug C attached thereto. Another lug D communicates the motion of the switch rail B to a bar G-Wl1l0l1 actuates contacts in a switch circuit controller E.

'This switch circuit controller comprises a pivoted member H provided with an insulated knob. H which operates the contacts E'-E Two dogs F are supported in the frame of the controller in such a manner as to be free to move horizontally and constrainedin any position only by inertia and friction. The pivoted member H has projections on its ends which may be engaged by said dogs in sliding contact as shown.

'The member H also carries a roller H which engages the top surface of the bar G and in this view is resting in the recess G in the top of the said bar, thus permitting the contacts E-E to be open. It is plain that this contact may be normally open or normally closed, and with a plurality of contacts there may be any desired combination of open'and closed contacts.

Fig. 2 shows the same apparatus but with the switch in the normal position. In this position the rail A and the switch rail B are in contact and the detector operating bar G has been moved to the right into a new position( The contacts EZ-E are still open he cause the roller H now rests in a second recess G in the bar G, but it is plain that it must have been closed during the motion from the position shown in Fig. 1 to that shown in Fig. 2, for in making this change the roller H must have been forced out of the recess G which it occupied, and rolled along the top of the bar G thereby tipping the member H, and closing the contacts by means of the insulated knob I-I. At the end of its motion, that is when the switch was fully closed the roller dropped into the recess G and released the contacts which opened again as shown at E-E The operation of this apparatus is as follows: In Fig. 3 the switch is in the normal position, but the rail B is tipped by a trailing vehicle wheel W. The flange of this wheel has swung the switch rail 13 into the position shown, thus deflecting the bridle rod 0 and moving the bar G, by means of the lug D, to the right by a small amount. This motion, thou h slight, is enough to force the shoulder on the bar G into engagement with the dog F which pushes the tip H of the member H upwards, closing the contacts E-E and, even though the switch rail may spring back partly or fully to its normal position, this member will remain in this position, for the tip H of the member H now rests upon the top surface of the dog F whereby it is retained in this position. This position can only be changed by an authorized person and till such action has been taken the fact that a train has trailed through the switch will be indicated by any suitable apparatus controlled by contacts IS -E In Fig. 4.- I show another form of apparatus embodying my invention. In this view the switch point B, shown in the reverse position is operated by the lug C" on the bridle rod C and is connected to a standard goose neck switch circuit controller bar G. Connected to the bridle rod G as shown and placed adjacent and parallel to the bar G is a second bar M. Recesses G G and G are cut in the top of the bar G and similar recesses M M and M are cut in the top of the bar M. These recesses are so disposed that normally as shown in Fig. e the recess G alignswith M G with M and G with M thus permitting the rollers K and H to rest in said recesses. A pivoted member H is arranged so that when the rollerI 2 is pushed out of a pair of recesses it will close the contacts E-E by means of an insulated knob H.- Another pivoted member L, having its lower surface plane and parallel to the tops of the bars G and M in its normal position, rides upon a roller K, which rests in the recess G M This member L is also provided with an insulated knob L which bears against the contact spring E In Fig. 5 the same apparatus is shown in the normal position, wherein the bridle rod C has drawn the switch rail B into contact with the rail A. During this motion, from the position shown in Fig. i to that shown in Fig. 5, the arm L has not been lifted since its lower surface is plane and horizontal and the roller K has simply moved along this surface, supported in the recess G -M the bars M and G and having sufiered no differential motion. But the roller H has been forced out of the recess (x -M closing the contacts EE by means of the insulated knob H, and now rests in the recess G -M with the contacts IEE open again.

In Fig. 6 I show the operation when a wheel IV of a vehicle trails through the switch. The flange of the wheel forces the rail B of the switch into some such position as that shown, causing the bar G to move longitudinally with respect to the arm M, which is rigidly attached to the bridle rod G. The result is that the recesses in the two bars no longer align and the roller K is lifted out of the recess G M forcing the arm L to move upward about its pivot, closing the contacts EE Arm L then becomes locked in this position by some restraining means, shown in the drawings as a hook O engaging another hook L fastened to the arm L. This differential motion of the two bars G- and M also lifts the roller H and hence the arm H helps to close the contacts E-E but when the wheel has passed the switch, if the rail 13 springs back into its normal position, the arm H will drop to its normal position. Arm L is held up against the contact by the latch O-L, however, and hence it holds the contact closed until released by an authorized person.

In Fig. 7 I show a slightly modified form of the device in which, instead of the rod M, I use a rod P attached to the other switch rail B. The operation is the same as in Fig. 6 for any relative displacement of the two rods and provides detection for both points.

Although I have herein shown and described only three forms of detecting device embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. A detection device for a railway switch comprising a member operatively connected to a rail of the switch, a contact, and means interposed between. said members and said contact for operating and retaining said contact when a wheel trails through the switch.

2. A detection device for a railway switch comprising a member operatively connected to a rail of said switch, means for causing sit) said member to move longitudinally when the said switch is trailed by a vehicle, and means for operating a contact mechanism by such motion and for maintaining the said mechanism in its operated position.

3. A detection device for a railway switch comprising a member having an upstanding lug, a sliding dog coacting therewith, a pivoted rocker arm operated by said dog, a contact mechanism, an insulated knob on said pivoted arm for operating said contact mechanism, and means for operating said member to engage said dog when a vehicle trails through the switch.

4. A detection device for a railway switch, comprising means for creating a difierential motion when the switch is trailed by a vehicle, and a contact mechanism operated and locked by said means.

5. In combination, a switch rail, a contact, and means operating when said switch is trailed through by a vehicle for moving and locking said contact to a position corresponding to that of the transit of the switch.

6. In combination, a switch, a switch circuit controller, means of creating differential motion when the said switch is trailed through by a vehicle, and means of utilizing said motion to move and lock the contacts of the said switch circuit controller to the position corresponding to the normal transit of the switch.

7. In combination, a railway switch, a circuit controller, and means interposed be-- tween the movable rail of said switch and said circuit controller and responsive to the movement of said rail when a train trails through the switch for operating and retaining said circuit controller.

8. In combination, a member operatively attached to a rail of a railway switch, a second member operatively connected with the bridle rod of said switch, and means for indicating diiferential motion of said members.

9. In combination, a railway switch, a

' bridle rod for said switch, a member operatively connected with said bridle rod, a second member disposed adjacent said first member and operatively attached to a rail of said switch, an electrical contact, means for closing said contact while moving said switch from one position to the other and means for closing said contact when said first member and said second member suffer relative displacement.

10. In combination, a railway switch, a bridle rod for said switch, a member operatively connected with said bridle rod, a second member disposed adjacent said first member and operatively attached to a rail of said switch, a recess in the top of said first member normally registering with a similar recess in the top of the second said member, a roller normally resting in said recess, a pivoted member normally biased to a given position and having one end supported on said roller, means controlled by relative displacement of the two said members for moving said pivoted member into a new position, means for locking said pivoted member in such new position and contact mechanism controlled by said pivoted member.

11. In combination, a railway switch, a bridle rod for said switch, a member operatively connected with said bridle rod, a second member disposed adjacent said first member and operatively attached to a rail of said switch, a recess in the topof said first member normally registering with a similar recess in the top of the second said member, a roller normally resting in said recess, a pivoted member normally biased to a given position and having one end supported on said roller, means controlled by relative displacement of the two said members for moving said pivoted member into a new position, means for locking said pivoted member in such new position, a second and a third recess in the top of said first member normally registering with similar recesses in the top of said second memher, a second pivoted member provided with a roller which no-rmallyrests in the said second or third recess when said switch is open or closed respectively and resting on the top of the said bars when said switch is in an intermediate position, and contact mechanism operated by said pivoted members.

12. In combination, a railway switch, a contact, and means operated by the movement of the switch point to shift said contact to a given position and retain it in such position.

13. In combination, a railway switch, a member operatively connected with a rail of said switch and normally moving in unison with such rail, a contact, and means efiective in the event of relative movement of said rail and said member for shifting said contact, said means not being effective to shift the contact during movement of the rail and the member in unison.

14. In combination, a railway switch, a member operatively connected with a rail of said switch and normally moving in unison with such rail, a contact, and means efi'ective in the event of relative movement of said rail and said member for shifting said contact and retaining it in shifted position.

In testimony whereof I affix my signature.

HERBERT A. WALLACE. 

